Almost a quarter of smartphones sold were iPhones as Apple’s market share rose to 23.8 percent from 15.8 percent a year earlier, the Stamford, Connecticut-based researcher said. Apple sold 35.5 million smartphones to consumers while Samsung sold 34 million, Gartner said.

Global sales of such handsets that use computerlike processors and can handle business e-mail and streaming video increased 47 percent to 149 million units. Apple’s sequential growth may slow this quarter as pent-up demand was largely sated by holiday sales, Roberta Cozza, a Gartner analyst based in Egham, U.K., said in an interview.

“The wild card for 2012 is China,” Cozza said. “If Apple closes a deal with China Telecom or China Mobile they could see their units double in that market.”

Gartner forecast 39 percent growth in smartphones this year, slowing from 58 percent last year. Google Inc.’s Android software ran on more than half of all smartphones sold, according to Gartner.

Nokia Declines

Nokia Oyj’s smartphone market share fell to 12 percent, from about 30 percent a year earlier, putting it third, Cozza said. Nokia’s share declined as the Finnish company shifted its focus to Microsoft Corp.’s Windows Phone software and phased out the 10-year-old Symbian line.

The introduction of Nokia’s Lumia handsets didn’t stem a decline in Microsoft’s market share, which dropped to 1.9 percent from 3.4 percent in the fourth quarter, Gartner said. Cozza said she expects Windows Phone to reach an 8.6 percent share of smartphones by the end of the year.

Apple’s smartphone success made it the world’s third- largest vendor of handsets overall, passing LG Electronics Co., which fell to fifth place behind ZTE Corp. Nokia kept its position as the biggest vendor with a 23.4 percent share, narrowing its lead over Samsung Electronics Co. to 4 percentage points.

Gartner forecast overall mobile phone growth to be 7 percent this year, slowing from 11.1 percent in 2011.